1. Field of Invention
This invention is in the field of book holder, note holders, and stands that hold books open.
2. Description of Prior Art
Previous book holders and copy holders have been restrained for all practical purposes by a paradox: if they are adaptable to different books and successfully hold books open, they are often too complicated and difficult to use. If they are simpler in construction and easy to use, then they are often limited in application and ineffective.
One attribute of a good book holder is the ability to accommodate books of different thicknesses. U.S. Pat. No. 490,569 by Lehman, 24 Jan. 1893, achieves such a result by utilizing fixed page holders in front of the book, along with a spring equipped back rest behind the book, which pushes the book open against the page holders. Although a wide range of thicknesses are allowed by such a device, the page holders would tend to get in the way of turning the pages, making it cumbersome to use in practice.
Another version which can potentially hold thick books and does not require much space is U.S. Pat. No. 1,675,621 by Spencer, 3 July 1928. Spencer uses a wire frame as a base and backrest, and then hangs a wire book support from the horizontal crosswire at the top of the wire frame, thus allowing the entire book support to swing forward and backward relative to the backrest. The book support has a lip or page holder at the front of the section that the bottom of the book rests upon. When the book support swings back, the lip tends to press the pages back against the book and backrest.
Like Lehman, Spencer makes it cumbersome to turn pages, especially to flip through many pages. The permanent lips in these two book stands do not allow for full and free clearance to easily turn pages.
Bent wire in Spencer's design also makes it difficult to use for referring to smaller sized notepaper: The notepaper may fall through the bottom.
A common type of design which makes it relatively easy to turn pages is represented by U.S. Pat. No. 1,864,807 by Dahlgren, 28 June 1932. Dahlgren utilizes a spring loaded clip as a page holder, which can be pulled all the way down below the base upon which the book rests, thus facilitating the turning of pages. Although Dahlgren's stand has some flexibility in accommodating books of different thicknesses, it has some inherent limitations in practice. If Dahlgren's principle were used to build a stand that could hold widely varied thicknesses, it would have a very long lever arm in the clip, from the pivot point to the point of contact with the pages. A long lever arm is cumbersome to deal with. In addition, a long lever arm takes up significant space when it is folded down for page turning. These problems are also illustrated with U.S. Pat. No. 719,386 by Smith, 27 Jan. 1903.
Many book holders have the problem of being loaded with various adjustments: U.S. Pat. No. 3,991,967 by Sack, 16 Nov. 1976, for example. Sack's design appears to be effective at holding books open and accommodating different thicknesses. But it has about five different adjustments for the page holding mechanism. Sliding page press, clampable thickness adjustment, etc.
U.S. Pat. No. 4,378,102 by Portis, Jr. et al., 29 May 1983, has the advantage of simplicity and functionality. One problem, however, is that two page holders must be adjusted before a page can be turned. A page holder, consisting of a string with a weight attached at the bottom, hangs down from each side. Each string must be pulled from a groove in the shelf and put out of the way before a page or pages can be turned.
The above mentioned Prior Art represent some of the best designs in the field. There are many other similar book holders which have problems similar to the ones outlined above. These include:
U.S. Pat. No. 97,710 by Sherman, 7 Dec. 1869; PA0 U.S. Pat. No. 298,039 by Swartz, 6 May 1884; PA0 U.S. Pat. No. 1,245,890 by Dunmar, 6 Nov. 1917; PA0 U.S. Pat. No. 1,300,045 by Tavi, 8 Apr. 1919; PA0 U.S. Pat. No. 2,691,240 by Kraus, 12 Oct. 1954; PA0 U.S. Pat. No. 4,123,029 Gillotti, 31 Oct. 1978; PA0 U.S. Pat. No. 4,145,022 by Comfort, 20 Mar. 1979. PA0 (a) which has a book support system capable of holding books in an open upright position, and to hold notepaper and other reading material in an upright position; PA0 (b) which holds the pages open, and allows for the easy turning of a page or flipping through of many pages, without blockage by the page press; PA0 (c) which holds the pages open in an effective manner by means of contoured page press; PA0 (d) which easily and automatically adjusts to different sized and very thick books without having to readjust the stand each time a different book is inserted; PA0 (e) which has built in bookmarks to keep track of several reference areas simultaneously; PA0 (f) which requires a minimum amount of natural uncomplicated hand motions for its operation; PA0 (g) which as one embodiment uses a minimum of desk space. PA0 (h) which as another embodiment has several accessible book holders in one revolving unit, such that each book holder contains objects and advantages (a) through (f).